Emerson Fisher FIELDVUE DVC2000, Инструкция по эксплуатации

Страница: 47 / 106

Detailed Setup and Calibration
July 2009 4-7
TRAVEL
RANGE
HIGH
TRAVEL
RANGE
LOW
THE SHAPE OF
THESE LINES DEPENDS ON
THE INPUT CHARACTERISTICS
LINEAR CHARACTERISTIC SHOWN
INPUT RANGE
LOW INPUT RANGE
HIGH
ANALOG INPUT
mA OR % OF 4-20 mA
CALIBRA
TED TRA
VEL,
%
A6531-1 / IL
Figure 4-1. Calibrated Travel to Analog Input Relationship
ZCS = CLOSED
ZCS = OPEN
NOTE:
ZCS = ZERO CONTROL SIGNAL
LUI Pressure Units—Enter the pressure units
displayed on the local user interface; psi, bar, or kPa.
Temp Units—Degrees Fahrenheit or Celsius.
The temperature measured is from a sensor mounted
on the digital valve controller’s printed wiring board.
Actuator and Valve Information
Select Setup & Diag, Detailed Setup, and Actuator &
Valve. Follow the prompts on the Field Communicator
display to enter or view information in the following
fields: Max Supply Press (Maximum Supply Pressure),
Actuator Style, Valve Style, and Zero Ctrl Signal (Zero
Control Signal).
Max Supply Press—Enter the maximum supply
pressure in psi, bar, or kPa, depending on what was
selected for pressure units.
Note
If the actual measured pressure
exceeds this setting by 25%, the
pressure measurement will not be
displayed.
Actuator Style—Enter the actuator style, spring
and diaphragm, piston double-acting without spring,
piston single-acting with spring, or piston double-acting
with spring.
Valve Style—Enter the valve style, rotary or
sliding-stem
Zero Ctrl Signal—Identifies whether the valve is
fully open or fully closed when the input is 0%. If you
are unsure how to set this parameter, disconnect the
current source to the instrument. The resulting valve
travel is the Zero Control Signal. (With direct acting
digital valve controllers, disconnecting the current
source is the same as setting the output pressure to
zero.)
Setting Response
Select Setup & Diag, Detailed Setup, and Response
Control. Follow the prompts on the Field
Communicator display to configure the following
response control parameters: Tuning Set, Damping
Factor, Expert Tuning Gains, Input Char (Input
Characteristic), Set Pt Filter Time (Set Point Filter
Time), Min Open/Close (Minimum Opening Time /
Minimum Closing Time), and Integral Settings.
WARNING
Changes to the tuning set may cause
the valve/actuator assembly to stroke.
To avoid personal injury and property
damage caused by moving parts,
keep hands, tools, and other objects
away from the valve/actuator
assembly.
Tuning Set—There are eleven tuning sets to
choose from. Each tuning set provides a preselected
value for the digital valve controller gain settings.
Tuning set C provides the slowest response and M
provides the fastest response. Table 3-4 lists the
proportional gain, velocity gain, and minor loop
feedback gain values for preselected tuning sets.
Damping Factor—If after selecting a tuning set
the valve travel overshoot is excessive or
unsatisfactory, the damping factor allows you to either
decrease damping to allow more overshoot, or
increase damping to decrease the overshoot.
Expert Tuning Gains—With Expert Tuning, you
can specify the proportional gain, velocity gain, and
minor loop feedback gain.
Input Char—Defines the relationship between the
travel target and ranged set point. Ranged set point is
4